queue.h File Reference

Double-ended queue. More...

Typedefs
typedef _Queue	Queue
	A double-ended queue.
Functions
Queue *	queue_new (void)
	Create a new double-ended queue.
void	queue_free (Queue *queue)
	Destroy a queue.
void	queue_push_head (Queue *queue, void *data)
	Add data to the head of a queue.
void *	queue_pop_head (Queue *queue)
	Remove data from the head of a queue.
void *	queue_peek_head (Queue *queue)
	Read data from the head of queue, without removing it from the queue.
void	queue_push_tail (Queue *queue, void *data)
	Add data to the tail of a queue.
void *	queue_pop_tail (Queue *queue)
	Remove data from the tail of a queue.
void *	queue_peek_tail (Queue *queue)
	Read data from the tail of queue, without removing it from the queue.
int	queue_is_empty (Queue *queue)
	Query if any data is currently in a queue.

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Detailed Description

Double-ended queue.

A double ended queue stores a list of pointers in order. New data can be added and removed from either end of the queue.

To create a new queue, use queue_new. To destroy a queue, use queue_free.

To add data to a queue, use queue_push_head and queue_push_tail.

To read data from the ends of a queue, use queue_pop_head and queue_pop_tail. To examine the ends without removing data from the queue, use queue_peek_head and queue_peek_tail.

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Function Documentation

void queue_free (  Queue *  queue  )

Destroy a queue. Parameters: queue  The queue to destroy.

int queue_is_empty (  Queue *  queue  )

Query if any data is currently in a queue. Parameters: queue  The queue. Returns: Zero if the queue is not empty, non-zero if the queue is empty.

Queue* queue_new (  void   )

Create a new double-ended queue. Returns: A new queue.

void* queue_peek_head (  Queue *  queue  )

Read data from the head of queue, without removing it from the queue. Parameters: queue  The queue. Returns: Data at the head of the queue, or NULL if the queue is empty.

void* queue_peek_tail (  Queue *  queue  )

Read data from the tail of queue, without removing it from the queue. Parameters: queue  The queue. Returns: Data at the tail of the queue, or NULL if the queue is empty.

void* queue_pop_head (  Queue *  queue  )

Remove data from the head of a queue. Parameters: queue  The queue. Returns: Data at the head of the queue, or NULL if the queue is empty.

void* queue_pop_tail (  Queue *  queue  )

Remove data from the tail of a queue. Parameters: queue  The queue. Returns: Data at the head of the queue, or NULL if the queue is empty.

void queue_push_head (  Queue *  queue, void *  data )

Add data to the head of a queue. Parameters: queue  The queue. data  The data to add.

void queue_push_tail (  Queue *  queue, void *  data )

Add data to the tail of a queue. Parameters: queue  The queue. data  The data to add.

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